Pruning rose bushes and deadheading faded flowers is a regular part of caring for a rose bush. According to the Virginia Cooperative Extension, "For maximum effectiveness, sharpen blades regularly and dry and oil them after each use." Sharpened rose pruners make a clean cut and will not damage the rose by crushing the stem. Besides being sharpened after each use, rose pruners should be sharpened in the spring, before they are used for the first time and before the pruners are stored for the winter.
Open the rose pruners completely. Hold them so the blade edge to be sharpened faces away from you.
Place the tip of the hand file on the edge of the blade nearest the pruner's hinge. Hold the file at an angle that approximates the angle of the edge.
Move the file over the edge of the blade. Use short strokes, always going in one direction. Continue filing until the blade's edge is shiny. Move the file to the next point on the blade and sharpen it; continue until the entire blade has been sharpened.
Turn the pruners over. Sharpen the other side of the blade.
Sharpen the second blade on pruners that have two blades. This will not be necessary for pruners that have one sharp side and one dull, hook-like side.
Run your finger lightly over the blade, checking for burrs. Be careful, as burrs can cut your skin.
Spray a light coat of lubricating oil over the sharpened blade. Wipe the blade with a cleaning cloth.